The objectives of this research are to determine quantitative information regarding the interface mechanics of biological prosthetic attachment. The materials used to achieve a direct bone implant interface are LTI pyrolytic carbon, carbon coated porous Co-Cr-Mo alloy and Bioglass. Intramedullary implants of these materials have shown significant alterations in the strain distribution of the proximal femur and marked bone remodelling after 8 months implantation. Good agreement between the experimental observations and analytical calculations of strain distribution using the finite element stress analysis technique has been found. Histomorphinetic analyses are now in progress to quantitate the bone response. Further studies are to be conducted to determine the effect of pore size, and porous coating thickness on the interface mechanics. In addition, the interface shear strength and deformation characteristics of the three attachment systems are to be measured.